This invention relates to wire tying tools and more particularly comprises a new and improved hand held assembly which is powered by an electric motor contained in the handle. The handle also contains rechargeable batteries for portable and safe operation of the tool.
Wire ties are extensively used both as bag ties and bar ties for such diverse purposes as binding sacks, linking snow fence slats, bundling rods and joining reinforcing rods. And a wide variety of tools are available for twisting the ties. These tools include very simple devices that have rigidly connected hooks and handles that are operated by turning the handle and more complex devices that include screw connections between the hooks and handles along with spring returns which enable the user to twist the wire by a pumping action on the handle. These devices are slow and require considerable work on the part of the user.
One important object of this invention is to provide an inexpensive, electrically powered, portable, light weight and safe hand tool which will reduce the manual labor and time involved in tying metallic bag ties and bar ties.
Another object of this invention is to provide an automatic tool which will make tighter and more uniform twists in the wire ties to which it is applied than can be obtained by the various manually operated tying tools presently available.
Still another object of this invention is to provide a wire tying tool whose power is available only when it is properly engaged with a tie.
To accomplish these and other objects, the automatic tying tool of this invention has among its many features a hook positioned on a shank which protrudes from the head of the handle and which is axially connected to the shaft of the electric motor located within the handle. The electric motor and the attached shank and hook are urged rearwardly in the handle by a spring located forward of the motor in the handle. When the hook engages a tie and a pulling force away from the wire is applied to the handle, the spring is compressed and the motor takes up a more forward position within the handle. This relative displacement of the handle and the motor activates a switch capable of closing the motor circuit. In this configuration, the tool can operate only when the hook is engaged in a tie and the handle is being drawn away from the wire. When activated in that manner, the motor causes the hook to rotate, thus tightly twisting the connected wire tie.
In order to increase the safety and life of the tool, a second, manual, on-off switch is provided in series with the switch actuated by relative displacement of the motor and handle.
For convenience and portability the tool is powered by rechargeable batteries housed in the handle; these batteries are recharged through an external socket placed in the rear of the handle in order not to hinder secure gripping of the handle by an operator.
These and other objects and features of this invention will be better understood and appreciated from the following detailed description of one embodiment thereof, selected for purposes of illustration and shown in the accompanying drawing, in which: